Tipped smoking article inspection



July 22, 1969 P|NKHAM ET AL $456,787

TIPPED SMOKING ARTICLE INSIFC'II'ON 4 Sheets-Sheet 1 Filed Feb. 1, 196'? INVENTORS JESSE R. DINKHAM LESLIE E. VNE DAVID H. HAL COUN sM ARTH BS WWW/1 July 22, 1969 R HNKHAM ET AL 3,456,787

TIPPED SMOKING ARTICLE INSPECTION Filed Feb. 1, 1967 4 Sheets-Sheet 2 INVENTORS JESSE R. PINKHAM LESLIE E. PAHNE DAVID H. MICHAL COLIN S. M ARTHUR Maw July 22, 1969 J. R. PINKHAM ET AL TIPPED SMOKING ARTICLE INSPECTION 4 Sheets-Sheet 5 Filed Feb. 1, 1967 NMELW m wM Amu w MM 0 2 6 W. E A 3 5 R HS 2 mmm r 5 SM I I I m w HU &.L D C I 7 V l B I/ 7 7 I x w v Q a/ Q fi n ZM% 5 July 1969 I P N ET AL TIPPED SMOKING ARTICLE INSPECTION Filed Feb. 1, 1967 4 Sheets-Sheet 4.

INVENTORS JESSE R. PINKHAM LESLIE E. PAYNE DAVID H-MICHAL COUN "5. MARTHUR EV WAQW United States Patent Otfice U.S. Cl. 20973 Claims ABSTRACT OF THE DISCLOSURE Cigarettes or other smoking articles having filter tips or other mouthpieces are submitted to non-destructive testing of the effectiveness or strength of the joint connecting the tip with the tobacco rod by gripping means gripping the cigarette on opposite sides of the joint and applying tension along the axis of the tipped cigarette sufiicient to permit detection of weak joints but not damage cigarettes having good joints, and testing and detecting which cigarettes have good joints and which have weak joints. Cigarettes having weak joints are diverted from the normal manufacturing path followed by the good cigarettes. Various methods and apparatus for testing for good cigarettes are disclosed.

Background of the invention In the manufacture of tipped cigarettes having as tips filters and/ or other devices, it is the common practice to make a double-length assembly, test it for leaks, and then sever the unit in half forming two identical tipped ciga rettes. The conventional making practice is to assemble in alignment two cigarette rods of the desired length and a double length mouthpiece tip section, usually containing filter material, located between the two cigarette rods. The ends of the two cigarette rods are brought into abutting relationship with the mouthpiece tip section. A band of sealing paper or other suitable material is then placed around the section of the mouthpiece tip with the edges of the band overlapping the ends of the cigarette rods. These overlapping edges are bonded or joined to the cigarette rods, usually with glue or other adhesive, thereby forming a double unit consisting of two cigarette rods with a double length mouthpiece tip section between them. The double unit is cut transversely at its center, resulting in two individual tipped cigarettes.

Because of the mechanical difliculties inherent in the problem of making a good bond with the sealing paper at the joint between the mouthpiece tip and the cigarette, particularly at modern production speeds of 1500 to 3000 cigarettes per minute and higher, it sometimes occurs that a leak develops at that joint, or the mouthpiece tip separates from the cigarette rod during use. A poor or weak joint of the mouthpiece tip to the cigarette rod can occur, for example, if the cigarette rod is slightly smaller than the mouthpiece tip, it the tobacco in the joint end of the cigarette rod is too soft, or if inadequate glue has been applied. Such an imperfection is difiicult to detect at the high production speeds used.

There are in use methods for inspecting for leaks in cigarettes, such as is described in United States Patent No. 2,951,364 to J. H. Sherrill dated Sept. 6, 1960; however, such methods exert an axial compressive force to the ends of the cigarette assembly and in so doing a joint sufficiently tight to pass as a quality cigarette can sometimes be made even when the joint is not adequately glued. Therefore, some weakly bonded joints of tip to cigarette rod are not detected by conventional inspection techniques. It is desirable to eliminate all such cigarettes having defective joints from the manufacturing process 3,456,787 Patented July 22, 1969 prior to packaging. To that end, it is preferable to test each cigarette for strength of joint of tip to cigarette rod and to withdraw it from the manufacturing line if a weak joint is found.

So far as applicants are aware, there is no method in commercial use for locating such weak joints other than a visual inspection to detect assemblies which have come apart. This is obviously inadequate since the overlapping sealing paper provides some strength to the joint even if insufiicient glue is present. Such a defective joint, weak enough to make the cigarette undesirable from the users standpoint but strong enough to pass visual inspection and normal manipulation during manufacturing and packaging, is thus so concealed that it is not detected. Throughout the process of making, handling and packaging the transfers and conveying of the cigarettesare gentle, even at high speeds, from the concave flutes of one transfer drum to those of another drum. The cigarette units are normally held on the flutes by suction which tends to hold the parts of the units together. When forces are applied, they usually are axial compressive forces such as occur during transfer of cigarettes in trays or bulk conveyor systems. It is economically impossible, in highspeed manufacture, to achieve careful visual inspection, much less handle each cigarette, to determine the sufliciency of the strength of the joint of the tip to the cigarette rod.

Summary of the invention Described herein are methods and apparatus for automatically testing tipped cigarettes having a mouthpiece tip portion joined to a cigarette rod portion to detect and reject cigarettes having a weakly bonded joint of tip to cigarette rod. The test is illustrated as applied to filter tip cigarettes, and is shown as being applied to dual cigarette units before they are cut apart. If should be obvious that the testing method and apparatus herein are equally applicable to units tipped with other type mouthpieces, and indeed to single tipped cigarette units as well as to multiple units. By making the test on double units, however, the number of tests necessary is reduced by one-half.

The present invention provides a method for testing tipped cigarettes having a mouthpiece tip portion joined to a cigarette rod portion to detect and reject cigarettes having a weakly bonded joint of the tip to the cigarette rod without interrupting the flow of good cigarettes along their normal path. The method comprises subjecting any cigarette in the path to tension along-the axis thereof sufiicient to part only those joints of less than'predetermined strength and diverting cigarettes having parted joints from the normal path. The testing is preferably effected by gripping means gripping any cigarette on either side of the joint, or both joints of a dual cigarette, and applying tension up toa predetermined maximum value to the joint(s), inspecting each cigarette so submitted to tension forthe presence of a parted joint, selectively diverting from the path those cigarettes having parted joints, and continuing advancement of cigarettes having unparted joints along their normal path of manufacturer.

A parted joint, as the term is used herein, is a joint in which there has been axial movement of the tip relative to the tobacco rod. The movement need not be sufli cient for the tip and the rod to be completely separated, but merely enough so that a weak joint may be detected, as by air leakage (pneumatically) or otherwise. A separated" joint is also a parted joint, but additionally, in a separated joint, there has been sufiicient movement so that the parts are no longerin contact with each other.

The maximum amount of tension to be applied must,

of course, be below the amount which would result in damage to a cigarette having a reasonably good joint. The tension required to part a joint having little or no glue will be quite small, therefore a lower limit on the value of tension would be meaningless. Experience has shown that a practical upper limit of the tension applied to good cigarettes is up to about 40 ounces. At high cigarette production rates, the bonding of the joint may not reach full strength in the time between formation of the joint and testing, e.g., because of insutficient curing time for glue, in which case the maximum tension applied may be lowered to about to 24 ounces. This lower maximum value of testing tension is usually sulfieient to part unglued or poorly glued joints but will not normally part properly formed joints even though maximum strength is not yet attained. The particular testing tension to be employed in testing a particular type of joint will depend upon the characteristics of the joint itself, of the glue or other adhesive and of the types of papers being used. It is apparent that a quick-curing adhesive is desirable so that there need not be an unduly long distance in the manufacturing line between the cigarette maker and testing of the joints by the method of this invention.

The present invention also provides apparatus for automatically inspecting tipped cigarettes for any defective joint of tip to cigarette rod. The apparatus of this invention comprises gripping means for gripping a tipped cigarette and applying tension to the joint in a longitudinal direction substantially along the axis of the cigarette, means for detecting whether the joint has parted and rejecting any cigarette having a parted joint. A preferred form of the apparatus of the present invention further comprises means for advancing a stream of cigarettes along a normal path, first and second resilient gripping means adapted to grip any cigarette in said path on opposite sides of a joint thereof, and force imparting means adapted to urge the first and second gripping means away from each other and apply a pre-determined maximum force to the joint in a direction substantially along the longitudinal axis of the gripped cigarette. A preferred resilient gripping means is a flexible cigarette-encircling member adapted to contract against a portion of a cigarette inserted within it and grip the cigarette. This type of gripping means tends to give a good grip and also serves as a substantially gas-tight sealing means as well so that air pressure may be used to test for parted joints.

Brief description of the drawings FIGURE 1 is a perspective view illustrating the principal parts of an embodiment of cigarette testing apparatus of the present invention, with certain parts omitted for purposes of clarity;

FIGURE 2 is an illustration of a portion of a cigarette manufacturing line having a transfer drum for carrying cigarette assemblies and transferring them to a testing drum, rejecting failing cigarettes and transferring good cigarettes on along the line;

FIGURE 3 is an illustration of a gripped cigarette assembly, a defective joint of which has parted as the result of tension applied to the assembly, the existence of the parted joint being detected by means of air pressure;

FIGURE 4 is a simplified illustration of alternate mechanical detecting means for detecting parted joints;

FIGURE 5 is a partial cross-sectional view taken on the line V-V in FIGURE 1 illustrating in greater detail a preferred embodiment of resilient gripping means which may be employed in apparatus of this invention, the gripping means being shown gripping a cigarette;

FIGURE 6 is another partial cross-sectional view, this one taken on the line VI--VI in FIGURE 1 illustrating the gripping means in retracted position in readiness for extending inward to encircle and grip a cigarette as is shown in FIGURE 5;

FIGURE 7 is a view of the bottom of one of the flange shoes taken on line VII-VII of FIGURE 1;

FIGURE 8 is a partial cross-sectional view of one end of an inspection drum similar to the drum shown in FIGURE 1 but having alternate gripping means and alternate means for establishing sealed pressure communication with the interior of cigarettes being tested to generate a test signal;

FIGURE 9 is a partial end view of the inspection drum of FIGURE 8 showing the alternate gripping means in more detail;

FIGURE 10 is a partial face view of an embodiment of cigarette end seal members which are employed in the apparatus illustrated in FIGURE 8 for establishing pressure communication with the interior of a cigarette while sealing the cigarette paper tube from significant leakage to the atmosphere;

FIGURE 11 is a cross-sectional View of the seal member of FIGURE 10 taken along line XI-XI; and

FIGURE 12 is an illustration of alternate method and means for detecting parted joints and rejecting faulty cigarettes from the manufacturing line.

Description of the preferred embodiments The terms mouthpiece, tip or mouthpiece tip as used herein are generic terms meant to include ordinary filter plugs of any type filter material or materials, open mouthpiece sections with or without filter material therein, mechanical filtering devices having orifices, plates, etc., and cigar mouthpieces or stems, and the like. As employed herein, the term cigarette is a generic term inclusive of a filter tipped cigarette or a cigarette tipped with any type mouthpiece joined to the tobacco rod, as well as a single length or multiple length cigarette. The term is also intended to include any self-contained smoking article, such as a mouthpiece tipped cigar, which may be tested in accordance with the invention. The terms parted and separated have been defined above.

Referring to FIGURE 1, a conveyor-inspection drum 10 is shown carrying a plurality of double length tipped cigarettes 11 thereon, each of which is to be inspected for joint strength. Each dual tipped cigarette typically comprises tobacco-filled cigarette rod portions 11a and 1112 at the ends thereof separated by a double length mouthpiece tip section 110, usually a filter section, in the middle thereof and fastened together by means of tipping paper and adhesive. The tipping paper normally covers the entire mouthpiece section and overlaps each cigarette rod about 4 millimeters (mm.). Subsequently, each double length cigarette is cut in the middle of the tip section to produce two tipped cigarettes.

The drum assembly 10 is carried in bearing assemblies (not shown) which serve to mount the assembly to a frame (not shown). Rotatable drum 10 is continuously rotated by driving means (not shown). The drum 10 carries a plurality of rows of cradles 13 thereon, the rows being arranged around the circumference of the drum upon its outer surface. Only three rows of the cradles 13 have been shown for the sake of clarity; however, it is to be understood that rows of cradles surround the periphery of the drum 10 to support each of the cigarette assemblies shown in FIGURE 1 and others as the drum rotates. Each cradle 13 is advantageously concave and semi-cylindrical so as to cradle a portion of the cylindrical surface of one of the cigarettes 11 carried on the drum. The central pair of cradles 13 in each row are connected together to form an elongated cradle which receives the cylindrical surface of substantially the entire mouthpiece portion 11c of the double length cigarette. The purpose of this is to provide a suction chamber of a sort to provide resistance to longitudinal movement of the tip section 110 during the tension test. There are cradles 13 supporting each tobacco rod section 11a and 11b so that an individual section will be controllably carried by the drum 10 even if it is separated from the remainder of the cigarette assembly by failure of a joint during the tension test.

Each cradle 13, other than the central elongated cradle, has a central holding orifice, exemplified and illustrated by 13:: on FIGURE 1, opening underneath the cigarette in the cradle. Each of the central elongated cradles has a pair of such orifices, however this is not critical. One or more orifices, or a slit, could be used. Each row of cradles on drum 10 is provided with such orifices. Internal passageways 32 (FIGURES and 6) within the drum 10 selectively connect the holding orifices (by appropriate valve and port action to be described in more detail below) to a source of vacuum and, at'appropriate times, to a source of gas pressure (typically air) to eject cigarettes from the drum, either for rejection or for transfer to another drum. Thus each cigarette 11, or a portion thereof, is either held on the cradles 13 by vacuum applied to the orifices or ejected from the cradles 13 by positive gas pressure applied to the orifices.

FIGURE 2 shows in diagrammatic form how conveyorinspection drum 10 is included in the cigarette manufacturing line. The drum assembly 10 is adapted to receive a series of cigarettes from a drum assembly 14, which is provided with cradles and orifices similar to those of drum 10. The drum assembly 10 rotates clockwise, as shown by the arrow 16, while the drum assembly 14 rotates counterclockwise, as shown by arrow 17. The surfaces of the drum assemblies pass tangentially adjacent to each other at a cigarette transfer zone 18, and cigarettes are transferred from the drum assembly 14 to the drum assembly 10 by application of gas pressure to the orifices of drum 14 which are within the transfer zone 18 and simultaneous application of vacuum to the orifices of drum 10 which are also within the transfer zone 18. The cigarettes transferred to the drum assembly 10 are thereafter tested, as described below, as they pass through the testing zone 19 and are either rejected as being defective, illustrated by ejected cigarette 21, or are retained on the drum. The defective cigarette is ejected by a blast of gas from the orifices beneath it. Those cigarettes retained on the drum are thereafter transferred to a further drum assembly 22, similar to drum assembly 14, which rotates counterclockwise as shown by arrow 23. Cigarettes are transferred to the drum assembly 22 in transfer zone 24 by application of gas pressure to the orifices of drum assembly 10 which are in the transfer zone 24 and application of vacuum to the orifices of the drum assembly 22 which are also in the transfer zone 24.

Thus, the surfaces of the drum assemblies 14 and 22 are similarly formed with cradles and orifices, similar to those of drum assembly 10, to retain the cigarettes on or eject the cigarettes from the cradles. In the system of FIGURE 2, as each cigarette on the drum 14 enters the transfer zone 18, it is subjected to a positive gas pressure ejecting that cigarette from the cradles on that drum onto the cradles of the drum 10. At the same time, the orifices in the cradles 13 on the drum 10 within the transfer zone 18 are subjected to vacuum to receive the cigarette from the drum 14 and to retain the transferred cigarette on the surface of the drum 10 in the cradles 13. In like fashion, the orifices on the drum 10 when in the transfer Zone 24 are subjected to positive gas pressure and the orifices in the cradles on the drum 22 are subjected t vacuum to transfer cigarettes from the drum 10 to the drum 22.

As is shown in FIGURE 1, the flange portions 25a and 25b of the drum 10 include a plurality of gripping members 26 positioned in line with each row of holders 13. Each gripping member is reciprocatively mounted in a corresponding passageway and is reciprocated by a driving mechanism outside the drum heads. The driving mechanism comprises a plurality of gripping members 26, each of which carries a cam-follower roller 30 adapted to contact cam 35, which is carried by the frame, and force each gripping member inwardly toward a cigarette at point 35a against springs 29 (FIGURES 5 and 6) which urge each gripping member outwardly. The springs 29 are calibrated springs adapted to urge the gripping members outwardly with a force in the range of about 5 to 32 ounces. All the springs 29 are substantially identical so that consistent tension forces are applied to each cigarette.

Briefly, when a cigarette is transferred from the drum 14 to the inspection drum 10 as described above, the gripping members 26 positioned in the transfer zone 18 (FIG- URE 2) are in a retracted position. After the cigarette is transferred to the drum 10 and held on the holders 13 by vacuum via conduit 44, port 45 in end-shoe 62, and drum port 56 in communication with orifices 13a, the gripping members 26 are moved inwardly to their fully extended position to encircle the tobacco rod portions 11a and 11b of cigarette 11 transferred to drum 10. While gripping members 26 are in the extended position and encircling the end portion of the cigarette rod, corresponding flexible resilient members 31 (FIGURES 5 and 6) are expanded from the groove 33 and contracted against the cigarette rod by application of gas pressure (typically air) via port 32. Preferably, vacuum is briefly applied via port 32 while the gripping members 26 are being extended to expand the openings in resilient members 31 for free entrance of the cigarette rods 11a (FIGURE 6). The flexible gripping member 31 is suitably a toroidal rubber bladder fitted within groove 33 in member 26, the inside of the bladder being in flow communication with the port 32. Alternatively, the flexible gripping member may be a hollow cylindrical band of rubber or other suitable wear-resistant flexible material sealably retained in the groove 33, as shown in FIGURES 5 and 6.

A more detailed understanding of the operation of the embodiment of the inspection drum 10 shown in FIG- URE 1 may be gained by reading FIGURE 1 in conjunction with FIGURES 5, 6, and 7. As described above, gripping members 26 are reciprocatively mounted in and extend through flanges 25a and 25b of drum 10 and are urged outwardly toward the retracted position by coil springs 29. The springs 29 are normally designed to produce a force of about 12 ounces. Upon rotation of the drum 10, cam-follower rollers 30 sequentially contact the cam 35 and are forced inwardly at point 35a by the cam to move the gripping members 26 into cigaretteencircling extended position. FIGURE 6, which is a partial sectional view taken along line VIVI of FIG- URE 1 and looking in the direction of the arrows, shows the conditions which exist at a typical gripping member 26 just before it is extended into cigarette-encircling position. Port 32 (FIGURE 6) is registered with vacuum port 61a of stationary manifold shoe 62 mounted on the frame (not shown) as illustrated in FIGURE 1. Vacuum ports 61a and 61b are connected to a source of vacuum (not shown) via conduit 63. Vacuum ports 61a, 61b and pressure port 64 are machined into end-shoe 62 so that ports 32 on each of the gripping members 26 are sequentially registered with the ports of the end-shoe 62 as the drum 10 rotates. Each port 32 communicates with grooves 33 in gripping members 26 so that when vacuum is applied to port 32, the cigarette-receiving opening in flexible member 31'is enlarged for easy entrance of a Cigarette rod. Elongated vacuum port 61a remains in register with port 32 during that part of the rotation of the drum 10 which causes the cam follower roller 30 to ride inward on the cam 35 (FIGURE 1) and extend the gripping member into cigarette-encircling position as shown in FIGURE 5. At this point, port 32 passes beyond vacuum port 61a (FIGURE 1) and enters register with pressure port 64 which is connected to a source of gas pressure (not shown) via conduit 66. A gas pressure of about 1.5 p.s.i.g. is normally suitable, depending, of course, on the particular flexible material used and its area. The gripping pressure and area of the flexible member 31 should be correlated so that the member 31 neither slides on the cigarette nor crushes it.

As shown in FIGURES 5, upon register of port 32 with a source of gas pressure (port 64 in FIGURE 1) the gas pressure enters groove 33 and causes flexible member 31 to contract against and grip the cigarette rod. At point 35b (FIGURE 1) cam 35 curves away from cam-follower out of contact with the cam-follower permitting the springs 29 to urge the gripping members 26 outwardly, placing the dual cigarette, and thus the joints thereof, under tension.

The cigarette unit is tested for leaks while it is in this condition. If the joints are good, the unit will be under tension. Of course, if the unit comes apart because of a faulty joint, permitting the gripping members 26 to be partially retracted by the springs 29 until the cam followers 30 contact the cam 35, no tension will exist and this condition will be detected as a leak. The cam prevents the gripping members 26 from retracting fully in order to maintain register of the testing ports described below.

If one or both joints of cigarette 11 is defective, the defective joint is parted by the corresponding cigarette rod portion being moved relative to the mouthpiece section 110 by partial retraction of gripping members 26. If the joints do not fail, the flexible members 31 continue to grip the cigarette rod without inflicting damage thereto while simultaneously sealing the interior of the gripping member and the interior of the cigarette in flow communication without significant leakage to the atmosphere and subjecting the joints to tension. After the cigarette has been placed under tension, the parted joint detector is brought into play. As is illustrated in FIGURE 3, a parted joint is detected by subjecting both ends of cigarette 11 to positive gas (typically air) pressure, typically a pressure of about 10 inches of water, and determining the pressure within the cigarette. If air leaks out a parted joint, or out of any other defect, resulting in loss of pressure of a predetermined amount, typically a pressure losS of about 0.5 to 6.0 inches of water, this event is detected as described in copending application of C. S. McArthur, Jr. and Bruce McKnight, S.N. 155,162, filed May 18, 1966, and a signal is sent via a conventional memory system to cause the defective cigarette to be rejected from the drum 10 following complete retraction of the members 26 upon further rotation of the drum 10.

The pneumatic detector system is illustrated in FIG- URE l with air from a constant pressure source (not shown) passing via conduit 58 to the timing, pressurization, detection and memory system 57, which system is similar to that described in the above copending application. Pneumatic test pressure is passed via conduits 36 and 36a to stationary flange shoes 37 and 37a which are mounted to the frame (not shown). A view of the bottom of shoe 37 which faces the flange 25a is shown in FIGURE 7. Shoe 37a is, of course, the same or similar. The shoe 37 is mounted in position to register a slot 38 therein with the inside row of ports 39 in the periphery of flange 25a to connect the pneumatic test pressure air flow to port 40 (FIGURE 5) and thus to cigarette rod 11a, and, through the similar ports carried by flange 25b, to cigarette rod 11b. Alternatively, air may be passed into one end only of the cigarette and the build-up or loss of pressure, if any, detected at the other end. Also, if desired, the outside of the cigarette may be placed under reduced pressure (vacuum) and any reduction in pressure inside the cigarette, resulting from a parted joint or leak, detected at one or both ends of the ciragette to generate a defective-cigarette signal.

A preferred embodiment of a leak detection system for use in connection with this invention comprises a pneumatic circuit utilizing fluid amplifiers. The system utilizes a Schmitt trigger responsive to the pressure in conduits 36 and 36a which exits after about 10 milliseconds of time delay allowed for the pressure in the cigarete being tested to build up to about 10 inches of water. The Schmitt trigger controls a pair of NOR gates which in turn control a first flip-flop. An output flip-flop, having a greater output than the first flip-flop, is controlled thereby and either exhausts its output or applies it as a faulty cigarette signal to a memory system which later sends a delayed cigarette rejection signal via conduit 51 to actuate cam 52, or other suitable device, which in turn operates valve 53 to replace vacuum with pressure in conduit 54 leading to port 55.'The memory system times the arrival of gas pressure at port 55 in end-shoe 62 with the registration of the port 56 in flange 25a (FIGURES 5 and 6), which port communicates with the orifices 13a (FIGURE 1) under the faulty cigarette, causing its rejection by blowing it off flutes 13 as illustrated at 21 in FIGURE 2. Valve '53 is supplied with vacuum via branched conduit 44'and with pressure via conduit from sources not shown. If the detection system detects no substantial gas pressureloss from a cigarette, or a pressure loss of less than a predetermined value, valve 53 remains in its normal position maintaining vacuum in port 55 so that the good cigarettes are carried on around the drum 10 for transfer on down the manufacturing line. The timing, pressurization, detection and memory system is designated as 57 on FIGURE 1. The system is fed gas pressure via conduit 58 from a constant pressure source (not shown).

An alternative mechanical system for generating a parted-joint signal is illustrated in a simplified manner in FIGURE 4. A spring-loaded feeler 41 is positioned over each of the joints of the cigarettes 11 as they pass beyond the testing zone. The two feelers (only one is shown) are located slightly outside the ends of mouthpiece section so that as a parted joint, such as 42, which in this case must be parted far enough for the parts to be separated, passes beneath the feeler it will not be raised as it would be by passage of a good cigarette joint and this failure-to-be-raised event, through suitable switching means, generates a defective-cigarette signal which is sent to the defective-cigarette ejection system.

As the cigarettes 11 are passed beyond testing zone 19, the gas pressure on flexible member 31 is released through port 32 and vacuum applied via ports 61b and 32 to reopen flexible member 31. Members 26 are then fully retracted from the ends of the cigarettes 11 by springs 29 when cam-follower 30 passes beyond cam 35. To prevent any cigarette rod portion 11a or 11b, which may have separated from mouthpiece section 110 during testing and retracted with the corresponding member 26, or any dust, bits of tobacco, etc. from remaining caught therein, a short blast of gas is directed through the gripping member 26 via port 40 (FIGURE 6). This blast of gas clears each gripping member as each of the ports 43 in the outside row of ports in flanges 25a and 25b become registered with stationary shoes 59a and 59b (FIGURES 1, 5, and 6). Gas from a source (not shown) passes via conduits 60a and 60b through the stationary shoes 59a and 5%, respectively, which are like shoes 37 and 37a described above, thence through ports 40. The ports 40 are in communication with ports 43 when the gripping members are in retracted position, which can be seen by comparing FIGURES 5 and6.

'Asrotation of the drum 10 continues, defective cigarettes are ejected from the drum 10 as each port 56 passes end-shoe port 55, as described above, and good cigarette assemblies are transferred to drum 22, for further processing in the manufacturing line, by application of gas pressure to holding orifices 13a via conduit 46, port 47 in end-shoe 62, and port 56, in brief registration therewith, which communicates with the orifices 13a.

Alternate gripping means and alternate means for establishing sealed pressure communication with the interior of cigarettes to test for parted joints and/or other leaks is described below with reference to FIGURES 8 through 11. In this embodiment, a testing drum 10a accepts, carries and transfers cigarettes in the same manner as discussed above in connection with drum 10.

The resilient gripping members 101 of this embodiment comprise holding blocks 102a and 102b, each of which is provided with a transverse semi-cylindrical opening adapted to close upon and grip a cigarette rod when the blocks are brought together, as the lower gripper is shown in FIGURE 9. Each block is carried by a leaf spring 103 mounted on gripper frame 100 and adapted to urge the blocks together in closed position, thus the term resilient is descriptive of this embodiment also. The leaf springs 103 are positioned around each end of drum 10a so that a pair of gripping members may grip each end of a cigarette transferred onto the holders of the drum.

Prior to transfer of cigarette units onto the drum, a cam 104 permits the gripping members to retract outwardly to freely receive a cigarette 11 such as is shown in place at the right-side of FIGURE 8. After each cigarette is in place, cam 104 causes cam-follower 106 to push corresponding gripping members 101 inwardly toward the middle of the drum 10a against the force of leaf springs 107 by which the gripper frames 100 are carried on the drum 10a. This is illustrated at the left side of FIGURE 8. The gripping members are held open by lever 108 which carries and is actuated by cam-follower 109 riding on cam 111. After each cigarette is in place, the gripping members are at the inward position and drum 10a continues rotation to a lower position of cam 111, cam-follower 109 follows the cam down, moving the lever 108 and permitting the gripping blocks 102a and 10211 to grip the ends of the cigarette as shown at the lower gripper in FIGURE 9.

As the drum 10a continues rotation, cam 104 curves away from cam-follower 106 allowing the leaf springs to exert force outwardly on the corresponding gripper frame 100 carrying the gripping members gripping each end of the cigarette, thus placing the cigarette under tension. Leaf springs 107, which are all as near alike as practical, are designed to exert a force selected from the range of about to 32 ounces tension to the cigarettes.

Also carried by the gripper frames 100 are end-seal members 112 positioned outside the ends of each cigarette carried on drum a and shown in more detail in FIG- URES l0 and 11. Each end-seal member is provided with a cigarette-end-facing recess 113 over which is sealably mounted a flexible diaphragm 114 of rubber or similar material. The diaphragm 114 is provided with a central orifice 116 positioned to communicate with the interior of a cigarette, the paper tube wrapper of which is placed in sealed relationship with the diaphragm when it is pressed against the end of the cigarette. Each diaphragm is pressed against the end of a cigarette when the corresponding gripper-frame 100 is moved inwardly by the cam 104 as described above in reference to FIGURE 8.

The end-seal members 112 at each end of each cigarette being carried on the inspection drum 10a are used for communication with the interior of the cigarettes to generate good-cigarette or faulty-cigarette signals. The signals are generated in the same manner as described above in connection with the other preferred embodiment. Communication between the cigarette under test and the timing, pressurization, detection and memory system is accomplished via conduit 116 in flow communication with stationary shoe 117 which is mounted to the frame (not shown) and adapted to register with port 118 of end-seal members 112 as each of them pass through the testing zone illustrated in FIGURE 2. Faulty cigarettes are rejected from drum 100 by any means apparent to persons skilled in the art from the description of apparatus herein, e.g. by causing a cam to open the gripping means and applying air pressure through orifices below the faulty cigarette to blow it from the drum.

As a suitable alternative to the above method and apparatus for detecting parted joints, tension is applied at the ends of the units with suflicient movement so that any weak joint is separated. For most normal joints the axial movement necessary is about 4 mm. for each joint. The cigarette units are then released from the tension apparatus and caused, such as by gravity or momentum, to pass over rails, as illustrated in FIGURE 12, adapted to support good units 121, 122, 123, and 124 near their ends and convey them on down the manufacturing line. The pieces of faulty units having separated joints fall between the rails 126a and 126b, as illustrated at 127 and 128, and are thus diverted from the normal manufacturing path.

The invention has been described with reference to a number of forms, but this was for the purpose of illustration, not delineation.

What is claimed is:

1. A method for testing tipped cigarettes having a mouth-piece tip portion joined to a tobacco rod portion to detect and reject cigarettes having a weakly bonded joint of the tip to the tobacco rod without interrupting the fiow of good cigarettes along their normal path, which methodcomprises circumferentially engaging any cigarette in said path and subjecting same to tension substantially along the axis thereof sufficient to cause relative movement of the tip and tobacco rod only in Weak joints of less than pre-determined strength and diverting cigarettes having weak joints from said normal path.

2. The method of claim 1 wherein said testing is effected by circumferentially gripping any cigarette on either side of said joint thereof and applying tension up to a pre-determined maximum value to said joint, selectively diverting from said path those cigarettes having weak joints, and continuing advancement of good cigarettes along said normal path.

3. The method according to claim 1 wherein said tension is in the range of up to about 40 ounces.

4. The method of claim 1 further including applying a pneumatic leak test to said cigarette.

5. Apparatus for inspecting tipped cigarettes for any defective joint of tip tobacco rod, comprising: means for applying tension axially of said joint; means for pneumatically treating said cigarette for leakage; means for detecting the pneumatic leakage of said cigarette; and cigarette rejecting means responsive to said detecting means to reject any cigarette having a predetermined level of leakage.

6. The apparatus of claim 5 further comprising means for advancing a stream of cigarettes along a normal path, said tensioning means comprising first and second resilient means adapted to grip any cigarette in said path on opposite sides of said joint thereof, and resiliently biased means operative to urge at least one of said resilient gripping means away from the other to thereby apply a force to said joint in a direction substantially along the axis of the gripped cigarette.

7. The apparatus of claim 6 wherein at least one of said first and second resilient means is a flexible cigarette encircling member adapted to contract against a portion of a cigarette inserted therewithin and substantially hermetically couple said tensioning means with said cigarette in flow communication.

8. The apparatus of claim 5 wherein said means for detecting and rejecting comprises a pair of rails in spaced relationship over which good cigarettes pass and between which cigarettes having separated joints fall.

9. A method for testing tipped cigarettes having a mouthpiece tip portion joined to a tobacco rod portion to detect and reject defective cigarettes without interrupting the flow of good cigarettes along a normal path of travel comprising the steps of:

(a) subjecting any cigarette in said path to tension substantially along the axis thereof sufficient to cause relative movement of the tip and tobacco rod only if the joint between said portions is of less than a predetermined strength;

(b) thereafter subjecting the interior of the cigarette to a predetermined pneumatic pressure;

(c) detecting the level of pneumatic pressure in the cigarette during the application of the predetermined pressure; and

(d) moving from the normal path of travel any ciga- 1,977,239 10/1934 Molins 131-21 rette having a pressure level during detection out- 2,246,107 6/1941 Ruau 13121 X side an acceptable range. 2,284,117 5/1942 Best 13121 10. The apparatus of claim 6 wherein at least one of 2,951,364 9/1960 Sherrill 131-21 said first and second resilient means comprises a pair of 5 3,091,960 6/1963 Houda 73-95 blocks, each block being provided with a semi-cylindrical 3,237,444 3/1966 Kaeding et a1 13121 transverse recess adapted to mate with the recess of the 3,368,671 2/1968 Kaeding 209-75 X other block in cigarette gripping relationship, and at least one spring member adapted to urge at least one of said FOREIGN PATENTS Ward the 10 928,743 6/1963 Great Britain.

References Cited ALLEN N. KNOWLES, Primary Examiner UNITED STATES PATENTS 1.49 205 6/1924 Ekstrom et al. 209-7s 2,065,888 12/1936 Du Bruletal 131 21 15 73-95; 209-75 l i i. also.z aawaumamz taammbimaammmaz:

22 33 UNITED ST ATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,456, 787 Dated JLUJ Z2 1969 Inventor(s) Jesse R. Pinkham, Leslie E. Payrg, David H. Michal and Colin S. McArthur It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 4, line 38, delete and separated" and .nsert in place thereof ---and "separated"---.

Colunm 7, line 39, delete "S.N. 155,162, filed May 18, 1966," Lnd insert in place thereof ---S.N. 551, 162, filed May 18, 1966, [OW U. S. Patent No. 3,426,582, issued February 11, 1969,---.

Colurm 7, line 65, delete "ciragette" and insert in place :hereof --cigarette---.

Column 7, line 72, delete "cigarete" and insert in place :hereof --cigarette.

Claim 5, line 2, between "tip" and "tobacco", insert Claim 5, line 4, delete "treating" and insert in place :hereof ---testing--.

SIGNED RND SEALED MAY5 1910 (SEAL) Atteat:

wmxm E- souumm, m. Edward M. Fletdm, Ir- Comissioner or Patents Auesting Officer 

